Fluid filter element

ABSTRACT

A filter element is removably positionable within a filter housing that includes a standpipe extending therewithin and provided with a flow control valve. The filter element comprises a tubular filter media, a first end cap, a second end cap longitudinally spaced from the first end cap, and a center tube extending between the first and second end caps. The center tube has a substantially cylindrical body extending between opposite first and second ends of the center tube. The center tube has at least one inlet opening formed on the cylindrical body and a standpipe opening at the second end thereof adjacent to the second end cap through which the standpipe may be inserted longitudinally into the center tube. The center tube further has at least one actuator key provided to open the flow control valve of the standpipe.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to fluid filter assemblies in general, and, moreparticularly, to a fluid filter assembly including a replaceable, fluidfilter element that actuates a flow control valve in a standpipe of afilter housing.

2. Description of the Prior Art

Many types of fluid filters are known in the prior art. A popular typeof fluid filter construction is one that has a housing which encloses areplaceable filter element. Fluid, such as oil or fuel, is cleansed ofimpurities as it passes through filter media of the filter element. Thefilter media captures many of the impurities that are removed from thefluid. Other impurities collect on the surface of the media and falldownward into a bottom area of the filter housing from which they may beperiodically removed through a drain valve.

Periodically the filter element must be replaced. Such periodicreplacement ensures that the filter element will not become so loadedwith impurities that fuel flow is restricted. Replacing the element alsoensures that impurities are removed from fuel before it is delivered toother fuel system components such as fuel injection pumps and fuelinjectors, where such contaminants may cause severe damage.

Changing filter elements may pose problems however. One common problemis that disturbance of the spent element during replacement may causecollected impurities to fall off the element. In some designs, theseimpurities may travel into the outlet of the filter housing. As a resultthese contaminants may reach the components downstream in the fuelsystem. Another problem with certain prior art fuel filter constructionsis that changing the element may require a mechanic to have skincontact-with the fuel. It is desirable to minimize such contact whenchanging a filter element.

While known liquid filters have proven to be acceptable for variousvehicular applications, such devices are nevertheless susceptible toimprovements that may enhance their performance and cost. With this inmind, a need exists to develop improved fluid filter assembly thatadvance the art.

SUMMARY OF THE INVENTION

The present invention provides a new and improved fluid filter elementremovably positionable within a filter housing defining a filter chamberfor the filter element.

The filter housing includes a standpipe extending within the filterchamber. The standpipe is provided with a flow control valve forselectively controlling fluid flow through the standpipe.

The filter element in accordance with the present invention comprises atubular filter media circumscribing a central axis, a first end capsupporting the filter media at one end thereof, a second end caplongitudinally spaced from the first end cap and supporting the filtermedia at the opposite end thereof, and a center tube extending betweenthe second end cap and the first end cap. The center tube has asubstantially cylindrical body extending between opposite first andsecond ends of the center tube. The center tube also has at least oneinlet opening formed on the cylindrical body and a standpipe opening atthe second end thereof adjacent to the second end cap through which thestandpipe may be inserted longitudinally into the center tube.Furthermore, the center tube includes at least one actuator key providedto actuate the flow control valve of the standpipe.

Upon further study of the specification and appended claims, furtherfeatures and advantages of this invention will become apparent to thoseskilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the invention will become apparent froma study of the following specification when viewed in light of theaccompanying drawings, wherein:

FIG. 1 is a cross-sectional view of a fuel filter assembly in accordancewith a first exemplary embodiment of the present invention;

FIG. 2 is a cross-sectional view of a filter housing in accordance withthe first exemplary embodiment of the present invention;

FIG. 3 is a perspective view of a standpipe with a flow control valve inaccordance with the first exemplary embodiment of the present invention;

FIG. 4 is an exploded cross-sectional view of the standpipe with theflow control valve in accordance with the first exemplary embodiment ofthe present invention;

FIG. 5 is a top view of the standpipe with the flow control valve inaccordance with the first exemplary embodiment of the present invention;

FIG. 6 is a cross-sectional view of the standpipe in accordance with thefirst exemplary embodiment of the present invention taken along lines6-6 of FIG. 5 showing the flow control valve in a closed position;

FIG. 7 is a cross-sectional view of the standpipe in accordance with thefirst exemplary embodiment of the present invention showing the flowcontrol valve in an open position;

FIG. 8 is an exploded perspective view of a filter element in accordancewith the first exemplary embodiment of the present invention;

FIG. 9 is a cross-sectional view of the filter element in accordancewith the first exemplary embodiment of the present invention;

FIG. 10 is a top view of the filter element in accordance with the firstexemplary embodiment of the present invention;

FIG. 11 is a bottom view of the filter element in accordance with thefirst exemplary embodiment of the present invention;

FIG. 12 is a top view of a center tube of the filter element inaccordance with the first exemplary embodiment of the present invention;

FIG. 13 is a cross-sectional view of the center tube of the filterelement in accordance with the first exemplary embodiment of the presentinvention;

FIG. 14 is a bottom view of the center tube of the filter element inaccordance with the first exemplary embodiment of the present invention;

FIG. 15 is a cross-sectional view of a fuel filter assembly inaccordance with a second exemplary embodiment of the present invention;

FIG. 16 is a cross-sectional view of a filter housing in accordance withthe second exemplary embodiment of the present invention;

FIG. 17 is a perspective view of a standpipe with a flow control valvein accordance with the second exemplary embodiment of the presentinvention;

FIG. 18 is an exploded view of the standpipe with the flow control valvein accordance with the second exemplary embodiment of the presentinvention;

FIG. 19 is a cross-sectional view of the standpipe in accordance withthe second exemplary embodiment of the present invention showing theflow control valve in a closed position;

FIG. 20 is a cross-sectional view of the standpipe in accordance withthe second exemplary embodiment of the present invention showing theflow control valve in an open position;

FIG. 21 is an exploded perspective view of a filter element inaccordance with the second exemplary embodiment of the presentinvention;

FIG. 22 is a top view of the filter element in accordance with thesecond exemplary embodiment of the present invention;

FIG. 23 is a cross-sectional view of the filter element in accordancewith the second exemplary embodiment of the present invention;

FIG. 24 is a bottom view of the filter element in accordance with thesecond exemplary embodiment of the present invention;

FIG. 25 is a top view of a center tube of the filter element inaccordance with the second exemplary embodiment of the presentinvention;

FIG. 26 is a cross-sectional view of the center tube of the filterelement in accordance with the second exemplary embodiment of thepresent invention;

FIG. 27 is a bottom view of the center tube of the filter element inaccordance with the second exemplary embodiment of the presentinvention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The preferred embodiment of the present invention will now be describedwith the reference to accompanying drawings. For purposes of thefollowing description, the terms “upper”, “lower”, “top”, “bottom”,“upward”, “downward”, “vertical”, “horizontal” and derivatives of suchterms shall relate to the invention as oriented in FIG. 1. However, itis to be understood that the invention may assume various alternativeorientations, except where expressly specified to the contrary. It isalso to be understood that the specific devices and processesillustrated in the attached drawings, and described in the followingspecification are simply exemplary embodiments of the inventiveconcepts. Specific dimensions and other physical characteristicsrelating to the embodiments disclosed herein are not to be considered aslimiting, unless expressly stated otherwise.

FIG. 1 depicts a fluid filter assembly 10 in accordance with the firstexemplary embodiment of the present invention providing a radiallyoutside-in flow pattern. The fluid filter assembly 10 comprises a filterhousing 12 and a replaceable (or disposable) filter element 40 removablymounted within the filter housing 12, the combination of which providesthe filter assembly 10. The filter assembly 10 can be useful forremoving particulate and other contaminants from any type of fluidsystem. The present invention is particularly useful as a filterassembly for removing particulate and other contaminant from fuel suchas internal combustion engine fuel in an engine fuel system in a motorvehicle.

The filter housing 12, further illustrated in detail in FIG. 2, israther conventional and includes a cup-shaped (or annular) housing body14 having a central axis 11 and projecting from a closed end 17 to adistal, open end 15, and a housing lid 16 removably attached to thehousing body 14. Preferably, the lid 16 is threadedly attached to thehousing body 14. The housing body 14 and the lid 16 are formed frommaterials appropriate for the particular application, such as metal orhard plastic. The filter housing 12, i.e. the housing body 14 and thelid 16, defines a filter chamber (an interior cavity) 18 into which theremovable filter element 40 is mounted. Appropriate brackets and otherattachment structure can be provided as necessary on the filter housing12 to enable it to be fixed to an appropriate location in a supportstructure.

The filter housing 12 is provided with a fluid inlet port 20 and a fluidoutlet port 22 which direct fuel into and out of the filter housing 12.The filter assembly 10 is described above as providing the radiallyoutside-in flow pattern through the element 40, however it should beappreciated that the inlet and outlet to the filter assembly 10 could bereversed, and the filter element 40 could provide a radially inside-outflow pattern, if necessary or desirable for the particular application.

Fluid, such as oil or fuel, to be filtered is directed through the inletport 20 and into a peripheral region of the filter chamber 18 of thefilter assembly 10, between the housing body 14 and the filter element40. The oil or fuel then passes radially inward through the filterelement 40, where contaminants/particulate matters in the fuel areremoved, and the filtered fluid then passes through the outlet port 22to the downstream components of a lubrication or fuel system of theinternal combustion engine (not shown). Thus, the filter housing 12 isadapted to be connected to the lubrication or fuel system of theinternal combustion engine for receiving unfiltered oil or fuel via theinlet port 20 and returning filtered fluid back to the lubrication orfuel system via the outlet port 22.

The housing body 14 further includes a series of internal threads 15 aare provided at the open end 15. The housing lid 16 also includes aseries of external threads 16 a provided near an open end thereof. Thethreads 15 a of the housing body 14 cooperate with the threads 16 a ofthe lid 16 to enable the lid 16 to be easily screwed onto and off of thehousing body 14. An O-ring seal or gasket 21 is provided between thefilter housing components, i.e. the housing body 14 and the lid 16, toprovide a fluid-tight seal. The above is only one technique forattaching the lid 16 to the housing body 14, and other techniques arepossible as should be known to those skilled in the art.

Referring now to FIGS. 1-7, a standpipe 24 extends vertically upwardsubstantially coaxially to the central axis 11 of the filter housing 12.

The standpipe 24 includes substantially cylindrical standpipe body 25having an internal flow passage 26 in fluid communication with theoutlet port 22, and a flow control valve 32 adjacent to a distal end 28of the standpipe body 25. The flow control valve 32 is provided foropening and closing the filter chamber 18 of the filter housing 12 tothe outlet port 22 depending upon whether or not the filter element 40has been properly mounted to the filter housing 12. The standpipe body25 further includes one or more inlet openings 30 provided in a neckportion 29 of the standpipe body 25 formed the distal end 28 thereof influid communication with the internal flow passage 26 to allow filteredfluid to pass inward into the internal flow passage 26 of the standpipe24. Preferably two inlet openings 30 are provided in the neck portion 29of the standpipe body 25. An inner end 27 of the standpipe body 25 issealingly secured to the closed end 17 of the housing body 14 by anyappropriate means known in the art, such as by a threaded connection.The standpipe body 25 is formed of material, e.g. metal, such asaluminum, or hard plastic, appropriate for the particular application.

As illustrated in FIGS. 3-7, the flow control valve 32 includes aclosure element 34 mounted for axial movement along the neck portion 29of the standpipe body 25 between a closed (uppermost) position (shown inFIGS. 2, 3 and 6) and an open (lowermost) position (shown in FIGS. 1 and7). The closure element 34 is normally biased by a spring 35 to theclosed position for preventing fuel flow into the standpipe 24 throughthe inlet openings 30. The flow control valve 32 further includes anO-ring 36 for sealing the closure element 34 against the neck portion 29of the standpipe body 25, an actuator ring 37 provided with a pluralityof actuator arms 38, and a standpipe seal in the form of an O-ring 39.The actuator ring 37 is mounted about the neck portion 29 of thestandpipe body 25 between the closure element 34 and the spring 35.

The flow control valve 32 is sized so that the closure element 34 is inclose-fitting, movable relation with the neck portion 29 of thestandpipe body 25 of the standpipe 24. The closure element 34 is therebymade axially movable about the neck portion 29 of the standpipe body 25.The spring 35 mounted about the neck portion 29 of the standpipe body 25serves as biasing means for biasing the closure element 34 in theoutward direction toward the distal end 28 of the standpipe body 25. Thestandpipe body 25 of the standpipe 24 has an annular shelf 25 a againstwhich one end of the coil spring 35 bears, while the other end of thecoil spring 35 bears against the closure element 34 through the actuatorring 37 to hold the flow control valve 32 in the closed position.

As further illustrated in detail in FIGS. 4-7, the closure element 34has a substantially cylindrical inner wall 34 a slidingly engaging theneck portion 29 of the standpipe body 25, a plurality of actuatoropenings 34 b in a top portion 34 c thereof for receiving actuator keysof the filter element 40 that axially depresses the actuator ring 37against the bias of the spring 35 to allow fluid flow through the inletopenings 30 past the closure element 34 and into the internal flowpassage 26 of the standpipe 24.

The closure element 34, the standpipe 24 and the inlet openings 30therein operate together as the flow control valve 32 to control fluidcommunication between the filter chamber 18 inside the filter housing 12and the internal flow passage 26 of the standpipe 24. When the closureelement 34 is disposed in its uppermost position (or closed) juxtaposedto the standpipe seal 39, as shown in FIG. 2, the cylindrical portion 34a of the closure element 34 is disposed adjacent and in blockingrelation to the inlet openings 30. As a result, the flow control valve32 is closed and the fluid flow into the standpipe 24 is blocked.However, when the closure element 34 is moved away from the standpipeseal 39 downward into its open position, the inlet openings 30 of thestandpipe 24 are open, as shown in FIG. 1, which enables the fluid to beadmitted to the internal flow passage 26 of the standpipe 24. Fluidflows into the internal flow passage 26 of the standpipe 24 through theinlet openings 30, and eventually passes to the fuel outlet port 22 ofthe filter assembly 10.

The replaceable filter element 40 is removably mounted in the filterchamber 18 of the filter housing 12. The filter element 40 according tothe first exemplary embodiment of the present invention illustrated indetail in FIGS. 7-9, includes a ring of a continuous, tubular filtermedia 42 in generally surrounding relation of the standpipe 24 so as tocircumscribe the central axis 11. Preferably, the filter element 40 ismounted within the filter housing 12 substantially coaxially to thecentral axis 11. The filter media 42 may be one of several types offilter media material known in the art formed of an appropriate materialin an appropriate manner and adapted for removing impurities from fluidthat passes therethrough.

As shown in detail in FIGS. 8-14, the filter element 40 further includesa first (upper) end cap 44 at its upper end, and a second (lower) endcap 46 at its lower end. The end caps 44 and 46 are engaging andsupporting in fluid tight relation the ring of filter media 42 at theopposite ends thereof in a conventional manner using potting compound orsimilar adhesive material. The filter element 40 further includes acenter tube 48 extending vertically upward between the second end cap 46and the first end cap 44. The first end cap 44, the second end cap 46and the center tube 48 are preferably each formed of an appropriatematerial (such as plastic) in a conventional manner, such as by molding.Preferably, the center tube 48 is secured to the second end cap 46 byany appropriate manner known in the art, such as adhesive bonding,welding, etc. Alternatively, the center tube 48 is homogenously formedintegrally with the second end cap 46 as a single piece unitary member.The center tube 48 has a first end 48 a adjacent to the first end cap 44and a second end 48 b adjacent to the second end cap 46. The first end48 a of the center tube 48 has an end wall 56 substantiallyperpendicular to the central axis 11.

More specifically, as illustrated in detail in FIGS. 1, 8, 9 and 13, thecenter tube 48 has a first substantially cylindrical side wall portion50 adjacent to an inner peripheral surface of the filter media 42, and asecond substantially cylindrical side wall portion 52 of smallerdiameter than the first side wall portion 50. The first side wallportion 50 and the second side wall portion 52 are separated by a middlewall 54 substantially perpendicular to the central axis 11. Furthermore,the first side wall portion 50 is provided with one or more intake holes51, while the second side wall portion 52 is impervious.

The filter chamber 18 of the filter housing 12 is separated by thefilter element 40 into a contaminated, or unfiltered, inlet chamber 18 aand a clean, or filtered, exit chamber 18 b. As shown in FIG. 1, theinlet chamber 18 a is defined between an inner peripheral surface of thefilter housing 12 and the filter element 40, while the exit chamber 18 bis defined between the filter element 40 and the standpipe 24.

The first end cap 44 is provided with a central hole 45 adapted toreceive the first end 48 a of the center tube 48 therethrough. Anannular resilient seal, or grommet, 58 extends across the central hole45 in the first end cap 44 to an outer peripheral surface of the secondside wall portion 52 of the center tube 48. The second end cap 46 isprovided with a central hole 47 through which the standpipe 24 can beinserted longitudinally into the center tube 48. An annular resilientseal, or grommet, 60 extends across the central hole 47 to engage anouter peripheral surface of the standpipe 24. Thus, the seals 58 and 60seal the exit chamber 18 b between the center tube 48 and the standpipe24 against infiltration of contaminated fluid, as illustrated in FIGS. 1and 7. The annular seal 60 defines a central opening 61 which isdimensioned to accept the standpipe 24 into the center tube 48.

Furthermore, the center tube 48 includes one or more actuator keys 55formed integrally therewith and provided to mate with the actuator ring37 of the flow control valve 32 in the standpipe 24. The actuator keys55 are sized and arranged complementary to the actuator openings 34 b inthe closure element 34 so as to extend therethough and engage theactuator arms 38 of the actuator ring 37. Preferably, the actuator keys55 are homogenously formed integrally with the center tube 48 as asingle piece unitary member.

Preferably, the actuator keys 55 are formed in generally evenly-spacedannular arrangement extending downwardly, away from the middle wall 54into the first side wall portion 50 of the center tube 48 toward thesecond end 48 b thereof. The number and spacing of the actuator keys 55can vary depending upon the number and location of the actuator openings34 b in the closure element 34, and it is noted that only a singleprotrusion may be necessary in some applications.

When the filter element 40 is installed in the housing 12, the actuatorkeys 55 on the center tube 48 project through the actuator openings 34 bin the closure element 34 and engage the actuator arms 38 of theactuator ring 37. As the filter element 40 is pressed further toward theclosed end 17 of the filter housing 12, the actuator keys 55 force theactuator ring 37 and the closure element 34 axially away from thestandpipe seal 39 towards its open position, thereby compressing thespring 35 and opening the inlet openings 30 of the standpipe 24, asshown in FIG. 1, which enable the fluid to be admitted to the internalflow passage 26 of the standpipe 24. The length of the actuator keys 55necessary to move the actuator ring 37 to an appropriate axial distancein order to open the flow control valve 32 can be easily determined.

It should be appreciated that the filter element 40 without a properarrangement of the actuator keys 55 will not engage the actuator arms 38of the actuator ring 37, and the flow control valve 32 will remainclosed. It will not be possible to attach the lid 16 to the housing body14. Thus, the invention not only prevents the operation of the filterassembly 10 without the filter element 40 installed, but also preventsthe operation of the filter assembly 10 even if the filter element 40 isinstalled, but where the filter element 40 fails to have a properarrangement of actuator keys 55.

The end wall 56 into the center tube 48 is further provided with aseries of distinct, axially-extending flexible fingers, tabs or otherelements 60 corresponding to complementary projections 62 formed on aninterior cover top wall 64 of the lid 16 (see FIGS. 1 and 2). Thefingers 60 are provided for engaging the cover top wall 64 of the lid 16to retain the filter element 40 to the lid 16 during initial assemblyand for pressing the filter element 40 against the biasing force of themain spring 35, as illustrated in FIG. 1. As illustrated in FIGS. 8, 10and 12, four such fingers 60 are shown in a generally evenly-spacedannular arrangement extending outwardly, away from the end wall 56 ofthe center tube 48, however the number and spacing of the fingers 60 canvary depending upon the particular structural arrangement of the filterassembly 10, and it is noted that only a single finger 60 may benecessary in some applications. Preferably, both the actuator keys 55and the fingers 60 are homogenously formed from an appropriate material(such as plastic) unitarily with the center tube 48 as a single pieceunitary member in a conventional manner, such as by molding.

In operation of the filter assembly 10, when the filter element 40 isinstalled properly in the filter housing 12, as illustrated in FIG. 1,the unfiltered (contaminated) fluid flows into the inlet chamber 18 a ofthe filter housing 12 through the inlet port 20. The unfiltered fluidthen flows into a portion of the inlet chamber 18 a surrounding thefilter element 40 and subsequently radially inward through the filtermedia 42 and the intake holes 51 in the center tube 48 of the filterelement 40 in the outside-in flow pattern into the exit chamber 18 b andis cleansed of impurities. The clean fluid then travels from the exitchamber 18 b into the standpipe 24 through the open flow control valve32. The filtered fluid leaves the filter housing 12 through the outletport 22.

When it is desirable to change a spent filter element, the lid 16 isremoved (screwed off), and the filter element 40 can be easily accessedand replaced with a fresh filter element. To facilitate the easygrasping of the spent filter element, the flow control valve 32automatically pushes the spent filter element 40 outwardly a shortdistance by resilience of the spring 35. This also allows at least someof the fluid to drip off the filter element and remain in the filterhousing 12, rather than drip onto the surrounding area during filterelement removal.

A new filter element 40 is installed in the housing body 14 by placingthe center tube 48 of the new filter element 40 about the standpipe 24.The filter element 40 is then moved downward. Movement of the filterelement 40 into the filter chamber 18 causes the actuator keys 55 of thecenter tube 48 to align with the actuator openings 34 b in the closureelement 34 so that the actuator keys 55 project through the openings 34b and engage the actuator arms 38 of the actuator ring 37. As the filterelement 40 is pressed further toward the closed end 17 of the filterhousing 12, the protrusions 55 then force the closure element 34 axiallyaway from the standpipe seal 39, thereby compressing the spring 35. Theinner cylindrical wall 34 a of the closure element 34 moves axially awayfrom the inlet openings 30 of the standpipe 24, thereby opening the flowcontrol valve 32, as shown in FIGS. 1 and 7. This enables the fluid tobe admitted to the internal flow passage 26 of the standpipe 24.

FIGS. 15-27 of the drawings illustrate a second exemplary embodiment ofa fluid filter assembly, depicted with the reference numeral 110.Components, which are unchanged from, or function in the same way as inthe first exemplary embodiment depicted in FIGS. 1-14 are labeled withthe same reference characters. The fluid filter assembly 110 of FIG. 15substantially corresponds to the fluid filter assembly 10 of FIG. 1, andonly the portions, which differ, will therefore be explained in detailbelow, sometimes without describing detail since similarities betweenthe corresponding parts in the two embodiments will be readily perceivedby the reader.

More specifically, according to the second exemplary embodiment of thepresent invention illustrated in FIG. 15, the fluid filter assembly 110comprises a filter housing 112 and a replaceable (or disposable) filterelement 140 removably mounted within the filter housing 112, thecombination of which provides the filter assembly 110.

The filter housing 112, further illustrated in detail in FIG. 16, issubstantially similar to the filter housing according to the firstembodiment of the present invention and includes a cup-shaped housingbody 14 having a central axis 11 and projecting from a closed end 17 toa distal, open end 15, and a housing lid 16 removably attached to thehousing body 14. The filter housing 112, i.e. the housing body 14 andthe lid 16, defines a filter chamber (an interior cavity) 18 into whichthe removable filter element 140 is mounted.

As further illustrated in FIGS. 15 and 16, a standpipe 124 extendsvertically upward from a closed end 17 of the filter housing 112substantially coaxially to a central axis 11.

As illustrated in detail in FIGS. 17-20, the standpipe 124 includessubstantially cylindrical standpipe body 125 having an internal flowpassage 126 in fluid communication with the outlet port 22, and a flowcontrol valve 132 adjacent to a distal end 128 of the standpipe body125. The flow control valve 132 is provided for opening and closing thefilter chamber 18 of the filter housing 112 to the outlet port 22depending upon whether or not the filter element 140 has been properlymounted to the filter housing 112. The standpipe body 125 furtherincludes one or more inlet openings 130 provided in a neck portion 129of the standpipe body 125 formed adjacent to the distal end 128 thereofin fluid communication with the internal flow passage 126 to allowfiltered fluid to pass inward into the internal flow passage 126 of thestandpipe 124. Preferably four inlet openings 130 are provided in theneck portion 129 of the standpipe body 125. The standpipe body 125 issealingly secured to the closed end 17 of the housing body 14 by anyappropriate means known in the art, such as by a threaded connectionthrough a mounting flange 127 a provided at an inner end 127 of thestandpipe body 125. The standpipe body 125 is formed of material, e.g.metal, such as aluminum, or hard plastic, appropriate for the particularapplication.

The flow control valve 132 includes a closure element 134 mounted foraxial movement along the neck portion 129 of the standpipe body 125 andbiased by a spring 135 to a closed position for preventing fuel flowinto the standpipe 124 through the inlet openings 130. The flow controlvalve 132 further includes a gasket 136 disposed in a groove 125 a inthe standpipe body 125 for sealing the closure element 134 against thestandpipe body 125, a snap-ring 137 provided with a resilient snapmember 138, and a standpipe seal in the form of an O-ring 139. Thesnap-ring 137 is mounted about the neck portion 129 of the standpipebody 125 between the closure element 134 and the spring 135.

The flow control valve 132 is sized so that the closure element 134 isin close-fitting, movable relation with the neck portion 129 of thestandpipe body 125 of the standpipe 124. The closure element 134 isthereby made axially movable about the neck portion 129 of the standpipebody 125 between the closed position illustrated in FIG. 19 and an openposition illustrated in FIG. 20. The spring 135 mounted about thestandpipe body 125 serves as biasing means for biasing the closureelement 134 in the outward direction toward the distal end 128 of thestandpipe body 125, i.e. to the closed position of the flow controlvalve 132. The standpipe body 125 of the standpipe 124 has an annularshelf 125 c against which one end of the coil spring 135 bears, whilethe other end of the coil spring 135 bears against the closure element134 through the snap-ring 137 to hold the flow control valve 132 in theclosed position.

In the closed position of the flow control valve 132, the resilient snapmember 138 of the snap-ring 137 engages a groove 125 b in the standpipebody 125, as illustrated in detail in FIG. 19. As further illustrated indetail in FIGS. 15, 16; 19 and 20, the closure element 134 has asubstantially cylindrical inner wall 134 a slidingly engaging the neckportion 129 of the standpipe body 125, a plurality of actuator openings(or actuator slots) 134 b at an outer wall 134 c thereof for receivingactuator keys of the filter element 140 that axially depresses theclosure element 134 and the snap-ring 137 against the bias of the spring135 to allow fluid flow through the inlet openings 130 past the closureelement 134 and into the internal flow passage 126 of the standpipe 124.

The closure element 134, the standpipe 124 and the inlet openings 130therein operate together as the flow control valve 132 to control fluidcommunication between the filter chamber 18 inside the filter housing112 and the internal flow passage 126 of the standpipe 124. When theclosure element 134 is disposed in its uppermost (or closed) positionjuxtaposed to the standpipe seal 139, as shown in FIGS. 16 and 19, theinner wall 134 a of the closure element 134 is disposed adjacent and inblocking relation to the inlet openings 130. As a result, the flowcontrol valve 132 is closed and the fluid flow into the standpipe 124 isblocked. However, when the closure element 134 is moved away from thestandpipe seal 139 downward to its open position, shown in FIGS. 15, 17and 20, the inlet openings 130 of the standpipe 124 are open, whichenables the fluid to be admitted to the internal flow passage 126 of thestandpipe 124. Fluid flows into the internal flow passage 126 of thestandpipe 124 through the inlet openings 130, and eventually passes tothe fuel outlet port 22 of the filter assembly 110.

The replaceable filter element 140 is removably mounted in the filterchamber 18 of the filter housing 112. The filter element 140 accordingto the second exemplary embodiment of the present invention illustratedin detail in FIGS. 21-24, includes a ring of a continuous, tubularfilter media 142 in generally surrounding relation of the standpipe 124so as to circumscribe the central axis 11. Preferably, the filterelement 140 is mounted within the filter housing 112 substantiallycoaxially to the central axis 11. The filter media 142 may be one ofseveral types of filter media material known in the art formed of anappropriate material in an appropriate manner and adapted for removingimpurities from fluid that passes therethrough.

The filter element 140 further includes a first (upper) end cap 144 atits upper end, and a second (lower) end cap 146 at its lower end. Theend caps 144 and 146 are engaging and supporting in fluid tight relationthe ring of filter media 142 at the opposite ends thereof in aconventional manner using potting compound or similar adhesive material.The first end cap 144 has an end wall 156 substantially perpendicular tothe central axis 11. The second end cap 146 is provided with a centralhole 147 through which the standpipe 124 can be inserted longitudinallyinto the center tube 148.

The filter element 140 further includes a center tube 148 extendingvertically upward between the second end cap 146 and the first end cap144. The first end cap 144, the second end cap 146 and the center tube148 are preferably each formed of an appropriate material (such asplastic) in a conventional manner, such as by molding. The center tube148 has a first end 148 a adjacent to the first end cap 144 and a secondend 148 b adjacent to the second end cap 146. Preferably, the centertube 148 is secured to the first and second end caps 144 and 146 by anyappropriate manner known in the art, such as adhesive bonding, welding,etc. Furthermore, as illustrated in detail in FIGS. 21 and 26, thecenter tube 148 has a substantially cylindrical side wall portion 150adjacent to an inner peripheral surface of the filter media 142. Theside wall portion 150 is provided with one or more intake holes 151.

The filter chamber 18 of the filter housing 112 is separated by thefilter element 140 into a contaminated, or unfiltered, inlet chamber 18a and a clean, or filtered, exit chamber 18 b. As shown in FIG. 15, theinlet chamber 18 a is defined between an inner peripheral surface of thefilter housing 112 and the filter element 140, while the exit chamber 18b is defined between the filter element 140 and the standpipe 124.

Furthermore, the center tube 148 includes one or more actuator keys 155formed integrally therewith and provided to mate with the closureelement 134 of the flow control valve 132 in the standpipe 124. Theactuator keys 155 are sized and arranged complementary to the actuatorslots 134 b so as to extend therethough and engage the closure element134. Preferably, the actuator keys 155 are homogenously formedintegrally with the center tube 148 as a single piece unitary member.

Preferably, the actuator keys 155 are formed in generally evenly-spacedannular arrangement extending downwardly, away from the first end 148 aof the center tube 148 toward the second end 148 b thereof. The numberand spacing of the actuator keys 155 can vary depending upon the numberand location of the actuator slots 134 b in the closure element 134, andit is noted that only a single protrusion may be necessary in someapplications.

When the filter element 140 is installed in the housing 112, theactuator keys 155 on the of the center tube 148 project through theactuator openings 134 b and engage the closure element 134. As thefilter element 140 is pressed further toward the closed end 17 of thefilter housing 112, the actuator keys 155 force the closure element 134axially away from the standpipe seal 139, thereby compressing the spring135 and opening the inlet openings 130 of the standpipe 124, as shown inFIG. 15, which enable the fluid to be admitted to the internal flowpassage 126 of the standpipe 124. At the same time, the resilient snapmember 138 of the snap-ring 137 snaps out of the groove 125 b in thestandpipe body 125, as illustrated in FIG. 14B. The length of theactuator keys 155 necessary to move the closure element 134 to anappropriate axial distance in order to open the flow control valve 132can be easily determined.

It should be appreciated that the filter element 140 without a properarrangement of the actuator keys 155 will not engage the actuatoropenings 134 b of the closure element 134, and the flow control valve132 will remain closed. It will not be possible to attach the lid 16 tothe housing body 14. Thus, the invention not only prevents the operationof the filter assembly 110 without the filter element 140 installed, butalso prevents the operation of the filter assembly 110 even if thefilter element 140 is installed, but where the filter element 140 failsto have a proper arrangement of actuator keys 155.

Moreover, the filter element 140 includes an annular resilient seal 161shown in FIG. 23. The seal 161 is supported by the center tube 148 andlays adjacent and axially opposite the actuator keys 155. The seal 161is provided to seal the center tube 148 of the filter element 140against the outer wall 134 c of the closure element 134, as illustratedin FIG. 15. In other words, the seal 161 fluidly separates the exitchamber 18 b from the inlet chamber 18 a of the filter housing 112.

The end wall 156 into the first end cap 144 is further provided with aseries of distinct, axially-extending flexible fingers, tabs or otherelements 160 corresponding to complementary projections 162 formed on aninterior cover top wall 64 of the lid 16 (see FIGS. 15 and 16). The tabs160 are provided for engaging the cover top wall 64 of the lid 16 toretain the filter element 40 to the lid 16 during initial assembly andfor pressing the filter element 40 against the biasing force of the mainspring 135, as illustrated in FIG. 15. As illustrated in FIG. 22, foursuch tabs 160 are shown in a generally evenly-spaced annular arrangementextending outwardly, away from the end wall 156 of the first end cap144, however the number and spacing of the tabs 160 can vary dependingupon the particular structural arrangement of the filter assembly 10,and it is noted that only a single tab may be necessary in someapplications. Preferably, the tabs 160 are homogenously formed from anappropriate material (such as plastic) unitarily with the first end cap144 as a single piece unitary member in a conventional manner, such asby molding.

In operation of the filter assembly 110, when the filter element 140 isinstalled properly in the filter housing 112, as illustrated in FIG. 15,the unfiltered (contaminated) fluid flows into the inlet chamber 18 a ofthe filter housing 112 through the inlet port 20. The unfiltered fluidthen flows into a portion of the inlet chamber 18 a surrounding thefilter element 140 and subsequently radially inward through the filtermedia 142 and the intake holes 151 in the center tube 148 of the filterelement 140 in the outside-in flow pattern into the exit chamber 18 band is cleansed of impurities. The clean fluid then travels from theexit chamber 18 b into the standpipe 124 through the open flow controlvalve 132. The filtered fluid leaves the filter housing 112 through theoutlet port 22.

When it is desirable to change a spent filter element, the lid 16 isremoved (screwed off), and the filter element 140 can be easily accessedand replaced with a fresh filter element. To facilitate the easygrasping of the spent filter element, the flow control valve 132automatically pushes the spent filter element 140 outwardly a shortdistance by resilience of the spring 135. This also allows at least someof the fluid to drip off the filter element and remain in the filterhousing 112, rather than drip onto the surrounding area during filterelement removal.

A new filter element 140 is installed in the housing body 14 by placingthe center tube 148 of the new filter element 140 about the standpipe124. The filter element 140 is then moved downward. Movement of thefilter element 140 into the filter chamber 18 causes the actuator keys155 of the center tube 148 to align with the actuator openings 134 b inthe closure element 134 so that the actuator keys 155 project throughthe openings 134 b and engage the closure element 134. As the filterelement 140 is pressed further toward the closed end 17 of the filterhousing 112, the actuator keys 155 then force the closure element 134axially away from the standpipe seal 139, thereby compressing the spring135. The inner wall 134 a of the closure element 134 moves axially awayfrom the inlet openings 130 of the standpipe 124, thereby opening theflow control valve 132, as shown in FIGS. 15, 17 and 20. This enablesthe fluid to be admitted to the internal flow passage 126 of thestandpipe 124.

The foregoing description of the preferred embodiment of the presentinvention has been presented for the purpose of illustration inaccordance with the provisions of the Patent Statutes. It is notintended to be exhaustive or to limit the invention to the precise formsdisclosed. Obvious modifications or variations are possible in light ofthe above teachings. The embodiments disclosed hereinabove were chosenin order to best illustrate the principles of the present invention andits practical application to thereby enable those of ordinary skill inthe art to best utilize the invention in various embodiments and withvarious modifications as are suited to the particular use contemplated,as long as the principles described herein are followed. Thus, changescan be made in the above-described invention without departing from theintent and scope thereof. It is also intended that the scope of thepresent invention be defined by the claims appended thereto.

1. A filter element removably positionable within a filter chamberdefined by a filter housing, the filter housing comprising a standpipeextending within the filter chamber, said standpipe provided with a flowcontrol valve for selectively controlling fluid flow through saidstandpipe, said filter element comprising: a tubular filter mediacircumscribing a central axis; a first end cap supporting said filtermedia at one end thereof; a second end cap longitudinally spaced fromsaid first end cap and supporting said filter media at the opposite endthereof; and a center tube extending between said second end cap andsaid first end cap, said center tube having a substantially cylindricalbody extending between opposite first and second ends of said centertube, said center tube having at least one inlet opening formed on saidcylindrical body and a standpipe opening at said second end thereofadjacent to said second end cap through which said standpipe may beinserted longitudinally into said center tube; said center tube havingat least one actuator key having a portion located radially inwardlyfrom said center tube and provided to actuate said flow control valve ofsaid standpipe, wherein said at least one actuator key is locatedbetween said first and second end caps and setoff from said centralaxis.
 2. The filter element as defined in claim 1, wherein said flowcontrol valve includes at least one inlet opening in a distal end ofsaid standpipe fluidly connected to an outlet port of the filter housingfor directing filtered fluid from said filter element to the outletport.
 3. The filter element as defined in claim 1, wherein said at leastone actuator pin longitudinally extends inwardly into said center tubein the direction from said first end toward said second end thereof. 4.The filter element as defined in claim 3, wherein said at least oneactuator pin includes a plurality of actuator pins extending into saidcenter tube and circumferentially spaced apart.
 5. The filter element asdefined in claim 1, wherein said first and second end caps of saidfilter element are radially spaced from an inner peripheral surface ofsaid filter housing.
 6. The filter element as defined in claim 1,wherein said first end cap has a central hole therethrough and saidfirst end said of center tube extends trough said central hole in saidfirst end cap of said filter element.
 7. The filter element as definedin claim 6, further including an annular seal member circumferentiallybounding said central hole in said first end cap.
 8. The filter elementas defined in claim 1, wherein said first end cap has an end walldisposed in said first end of said center tube of said filter element.9. The filter element as defined in claim 1, wherein the center tubedefines a radially extending shoulder located between said first andsecond end caps, and wherein said at least one actuator key extends fromsaid radially extending shoulder.
 10. The filter element as defined inclaim 1, further including an annular seal member circumferentiallybounding said standpipe opening of said center tube.
 11. The filterelement as defined in claim 9, wherein the radially extending shoulderradially reduces a diameter of the center tube between a first side ofsaid shoulder and one of said first end cap and said second end cap. 12.The fluid filter assembly as defined in claim 1, wherein said filterhousing is provided with an inlet port in fluid communication with saidfilter chamber and an outlet port in fluid communication with aninternal flow passage of said standpipe.
 13. The fluid filter assemblyas defined in claim 1, wherein said at least one actuator key isprovided to mate with a complementary actuator opening in a closureelement of said flow control valve of said standpipe.
 14. A fluid filterassembly comprising: a filter housing defining a filter chamber; a standpipe extending upwardly into said filter chamber of said filter housing;said standpipe including an internal flow passage and provided with aflow control valve for selectively controlling fluid flow through saidstandpipe; and a filter element removably positionable within saidfilter chamber of said filter housing, said filter element comprising: atubular filter media circumscribing a central axis; a first end capsupporting said filter media at one end thereof; a second end caplongitudinally spaced from said first end cap and supporting said filtermedia at the opposite end thereof; and a center tube extending betweensaid second end cap and said first end cap, said center tube having asubstantially cylindrical body extending between opposite first andsecond ends of said center tube, said center tube disposed about saidstandpipe substantially coaxially with said central axis, said centertube having at least one inlet opening formed on said cylindrical bodyand a standpipe opening at said second end thereof adjacent to saidsecond end cap through which said standpipe may be insertedlongitudinally into said center tube; said center tube having at leastone actuator key provided to actuate said flow control valve of saidstandpipe for providing fluid communication between said filter chamberand said internal flow passage of said standpipe, wherein said at leastone actuator key is located between said first and second end caps anddistanced from said central axis.
 15. The fluid filter assembly asdefined in claim 1, wherein said filter housing includes a cylindricalcup-shaped bowl having a closed end and an opposite open end and a coverremovably attached to said open end of said bowl.
 16. The fluid filterassembly as defined in claim 14, wherein said filter housing is providedwith an inlet port in fluid communication with said filter chamber andan outlet port in fluid communication with said internal flow passage ofsaid standpipe.
 17. The filter element as defined in claim 1, whereinsaid at least one inlet opening of said center tube are radially formedon said cylindrical body such that fluid can radially enter said centertube through said at least one inlet opening.
 18. The filter element asdefined in claim 14, wherein said at least one inlet opening of saidcenter tube are radially formed on said cylindrical body such that fluidcan radially enter said center tube through said at least one inletopening.
 19. The filter element as defined in claim 14, wherein thecenter tube defines a radially extending shoulder located between saidfirst and second end caps, and wherein said at least one actuator keyextends from said radially extending shoulder.
 20. The filter element asdefined in claim 19, wherein the radially extending shoulder radiallyreduces a diameter of the center tube between a first side of saidshoulder and one of said first end cap and said second end cap.